/**
 * @license
 * Copyright 2019 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/**
 * @fileoverview Methods for graphically rendering a block as SVG.
 * @author fenichel@google.com (Rachel Fenichel)
 */
'use strict';

goog.provide('Blockly.blockRendering.Debug');

goog.require('Blockly.blockRendering.BottomRow');
goog.require('Blockly.blockRendering.InputRow');
goog.require('Blockly.blockRendering.Measurable');
goog.require('Blockly.blockRendering.RenderInfo');
goog.require('Blockly.blockRendering.Row');
goog.require('Blockly.blockRendering.SpacerRow');
goog.require('Blockly.blockRendering.TopRow');
goog.require('Blockly.blockRendering.Types');


/**
 * An object that renders rectangles and dots for debugging rendering code.
 * @package
 * @constructor
 */
Blockly.blockRendering.Debug = function() {
  /**
   * An array of SVG elements that have been created by this object.
   * @type {Array.<!SVGElement>}
   * @private
   */
  this.debugElements_ = [];

  /**
   * The SVG root of the block that is being rendered.  Debug elements will
   * be attached to this root.
   * @type {SVGElement}
   * @private
   */
  this.svgRoot_ = null;
};

/**
 * Configuration object containing booleans to enable and disable debug
 * rendering of specific rendering components.
 * @type {!Object.<string, boolean>}
 */
Blockly.blockRendering.Debug.config = {
  rowSpacers: true,
  elemSpacers: true,
  rows: true,
  elems: true,
  connections: true,
  blockBounds: true,
  connectedBlockBounds: true
};

/**
 * Remove all elements the this object created on the last pass.
 * @package
 */
Blockly.blockRendering.Debug.prototype.clearElems = function() {
  for (var i = 0, elem; (elem = this.debugElements_[i]); i++) {
    Blockly.utils.dom.removeNode(elem);
  }

  this.debugElements_ = [];
};

/**
 * Draw a debug rectangle for a spacer (empty) row.
 * @param {!Blockly.blockRendering.Row} row The row to render.
 * @param {number} cursorY The y position of the top of the row.
 * @param {boolean} isRtl Whether the block is rendered RTL.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawSpacerRow = function(row, cursorY, isRtl) {
  if (!Blockly.blockRendering.Debug.config.rowSpacers) {
    return;
  }

  this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
      {
        'class': 'rowSpacerRect blockRenderDebug',
        'x': isRtl ? -(row.xPos + row.width) : row.xPos,
        'y': cursorY,
        'width': row.width,
        'height': row.height,
        'stroke': 'blue',
        'fill': 'blue',
        'fill-opacity': '0.5',
        'stroke-width': '1px'
      },
      this.svgRoot_));
};

/**
 * Draw a debug rectangle for a horizontal spacer.
 * @param {!Blockly.blockRendering.InRowSpacer} elem The spacer to render.
 * @param {number} rowHeight The height of the container row.
 * @param {boolean} isRtl Whether the block is rendered RTL.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawSpacerElem = function(elem, rowHeight, isRtl) {
  if (!Blockly.blockRendering.Debug.config.elemSpacers) {
    return;
  }

  var width = Math.abs(elem.width);
  var isNegativeSpacing = elem.width < 0;
  var xPos = isNegativeSpacing ? elem.xPos - width : elem.xPos;
  if (isRtl) {
    xPos = -(xPos + width);
  }
  var yPos = elem.centerline - elem.height / 2;
  this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
      {
        'class': 'elemSpacerRect blockRenderDebug',
        'x': xPos,
        'y': yPos,
        'width': width,
        'height': elem.height,
        'stroke': 'pink',
        'fill': isNegativeSpacing ? 'black' : 'pink',
        'fill-opacity': '0.5',
        'stroke-width': '1px'
      },
      this.svgRoot_));
};

/**
 * Draw a debug rectangle for an in-row element.
 * @param {!Blockly.blockRendering.Measurable} elem The element to render.
 * @param {boolean} isRtl Whether the block is rendered RTL.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawRenderedElem = function(elem, isRtl) {
  if (Blockly.blockRendering.Debug.config.elems) {
    var xPos = elem.xPos;
    if (isRtl) {
      xPos = -(xPos + elem.width);
    }
    var yPos = elem.centerline - elem.height / 2;
    this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
        {
          'class': 'rowRenderingRect blockRenderDebug',
          'x': xPos,
          'y': yPos,
          'width': elem.width,
          'height': elem.height,
          'stroke': 'black',
          'fill': 'none',
          'stroke-width': '1px'
        },
        this.svgRoot_));
  }


  if (Blockly.blockRendering.Types.isInput(elem) &&
      Blockly.blockRendering.Debug.config.connections) {
    this.drawConnection(elem.connection);
  }
};

/**
 * Draw a circle at the location of the given connection.  Inputs and outputs
 * share the same colours, as do previous and next.  When positioned correctly
 * a connected pair will look like a bullseye.
 * @param {Blockly.RenderedConnection} conn The connection to circle.
 * @suppress {visibility} Suppress visibility of conn.offsetInBlock_ since this
 *     is a debug module.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawConnection = function(conn) {
  if (!Blockly.blockRendering.Debug.config.connections) {
    return;
  }

  var colour;
  var size;
  var fill;
  if (conn.type == Blockly.INPUT_VALUE) {
    size = 4;
    colour = 'magenta';
    fill = 'none';
  } else if (conn.type == Blockly.OUTPUT_VALUE) {
    size = 2;
    colour = 'magenta';
    fill = colour;
  } else if (conn.type == Blockly.NEXT_STATEMENT) {
    size = 4;
    colour = 'goldenrod';
    fill = 'none';
  } else if (conn.type == Blockly.PREVIOUS_STATEMENT) {
    size = 2;
    colour = 'goldenrod';
    fill = colour;
  }
  this.debugElements_.push(Blockly.utils.dom.createSvgElement('circle',
      {
        'class': 'blockRenderDebug',
        'cx': conn.offsetInBlock_.x,
        'cy': conn.offsetInBlock_.y,
        'r': size,
        'fill': fill,
        'stroke': colour,
      },
      this.svgRoot_));
};

/**
 * Draw a debug rectangle for a non-empty row.
 * @param {!Blockly.blockRendering.Row} row The non-empty row to render.
 * @param {number} cursorY The y position of the top of the row.
 * @param {boolean} isRtl Whether the block is rendered RTL.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawRenderedRow = function(row, cursorY, isRtl) {
  if (!Blockly.blockRendering.Debug.config.rows) {
    return;
  }
  this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
      {
        'class': 'elemRenderingRect blockRenderDebug',
        'x': isRtl ? -(row.xPos + row.width) : row.xPos,
        'y': row.yPos,
        'width': row.width,
        'height': row.height,
        'stroke': 'red',
        'fill': 'none',
        'stroke-width': '1px'
      },
      this.svgRoot_));

  if (Blockly.blockRendering.Types.isTopOrBottomRow(row)) {
    return;
  }

  if (Blockly.blockRendering.Debug.config.connectedBlockBounds) {
    this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
        {
          'class': 'connectedBlockWidth blockRenderDebug',
          'x': isRtl ? -(row.xPos + row.widthWithConnectedBlocks) : row.xPos,
          'y': row.yPos,
          'width': row.widthWithConnectedBlocks,
          'height': row.height,
          'stroke': this.randomColour_,
          'fill': 'none',
          'stroke-width': '1px',
          'stroke-dasharray': '3,3'
        },
        this.svgRoot_));
  }
};

/**
 * Draw debug rectangles for a non-empty row and all of its subcomponents.
 * @param {!Blockly.blockRendering.Row} row The non-empty row to render.
 * @param {number} cursorY The y position of the top of the row.
 * @param {boolean} isRtl Whether the block is rendered RTL.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawRowWithElements = function(row, cursorY, isRtl) {
  for (var i = 0, elem; (elem = row.elements[i]); i++) {
    if (Blockly.blockRendering.Types.isSpacer(elem)) {
      this.drawSpacerElem(
          /** @type {!Blockly.blockRendering.InRowSpacer} */ (elem),
          row.height, isRtl);
    } else {
      this.drawRenderedElem(elem, isRtl);
    }
  }
  this.drawRenderedRow(row, cursorY, isRtl);
};

/**
 * Draw a debug rectangle around the entire block.
 * @param {!Blockly.blockRendering.RenderInfo} info Rendering information about
 *     the block to debug.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawBoundingBox = function(info) {
  if (!Blockly.blockRendering.Debug.config.blockBounds) {
    return;
  }
  // Bounding box without children.
  var xPos = info.RTL ? -info.width : 0;
  var yPos = 0;
  this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
      {
        'class': 'blockBoundingBox blockRenderDebug',
        'x': xPos,
        'y': yPos,
        'width': info.width,
        'height': info.height,
        'stroke': 'black',
        'fill': 'none',
        'stroke-width': '1px',
        'stroke-dasharray': '5,5'
      },
      this.svgRoot_));

  if (Blockly.blockRendering.Debug.config.connectedBlockBounds) {
    // Bounding box with children.
    xPos = info.RTL ? -info.widthWithChildren : 0;
    this.debugElements_.push(Blockly.utils.dom.createSvgElement('rect',
        {
          'class': 'blockRenderDebug',
          'x': xPos,
          'y': yPos,
          'width': info.widthWithChildren,
          'height': info.height,
          'stroke': '#DF57BC',
          'fill': 'none',
          'stroke-width': '1px',
          'stroke-dasharray': '3,3'
        },
        this.svgRoot_));
  }
};

/**
 * Do all of the work to draw debug information for the whole block.
 * @param {!Blockly.BlockSvg} block The block to draw debug information for.
 * @param {!Blockly.blockRendering.RenderInfo} info Rendering information about
 *     the block to debug.
 * @package
 */
Blockly.blockRendering.Debug.prototype.drawDebug = function(block, info) {
  this.clearElems();
  this.svgRoot_ = block.getSvgRoot();

  this.randomColour_ = '#' + Math.floor(Math.random() * 16777215).toString(16);

  var cursorY = 0;
  for (var i = 0, row; (row = info.rows[i]); i++) {
    if (Blockly.blockRendering.Types.isBetweenRowSpacer(row)) {
      this.drawSpacerRow(row, cursorY, info.RTL);
    } else {
      this.drawRowWithElements(row, cursorY, info.RTL);
    }
    cursorY += row.height;
  }

  if (block.previousConnection) {
    this.drawConnection(block.previousConnection);
  }
  if (block.nextConnection) {
    this.drawConnection(block.nextConnection);
  }
  if (block.outputConnection) {
    this.drawConnection(block.outputConnection);
  }
  if (info.rightSide) {
    this.drawRenderedElem(info.rightSide, info.RTL);
  }

  this.drawBoundingBox(info);
};